(CG 2/61). That the aforesaid Tenet is contrary to the Mind of Aristotle (Book 2: God The Origin of Creatures) (Summa Contra Gentiles) (Aquinas, Thomas, St.)

UPON consideration of these words of Aristotle, Alexander determined the potential intellect to be some power in us, that so the general definition of soul assigned by Aristotle might apply to it. But because he could not understand how any subsistent intelligence could be the form of a body, he supposed the aforesaid faculty of potential intellect not to be planted in any subsistent intelligence, but to be the result of some combination of elements in the human body. Thus a definite mode of combination of the components of the human body puts a man in potentiality to receive the influence of the active intellect, which is ever in act, and according to him, is a spiritual being subsisting apart, under which influence man becomes actually intelligent. But that in man whereby he is potentially intelligent is the potential intellect: hence it seemed to Alexander to follow that the potential intellect in us arises from a definite combination of elements. But this statement appears on first inspection to be contrary to the words and argument of Aristotle. For Aristotle shows (De anima, III, iv, 2-4) that the potential intellect is unmingled with the body: but that could not be said of a faculty that was the result of a combination of bodily elements. To meet this difficulty Alexander says that the potential intellect is precisely the 'predisposition' (praeparatio, epit�deiot�s) which exists in human nature to receive the influence of the active intellect; and that this 'predisposition' is not any definite sensible nature, nor is it mingled with the body, for it is a relation and order between one thing and another. But this is in manifest disagreement with the mind of Aristotle, as the following reasons show:

3. Aristotle assigns these characteristics to the potential intellect: to be impressed by the intelligible presentation, to receive intelligible impressions, to be in potentiality towards them (De anima, III, iv, 11, 12): all which things cannot be said of any 'disposition,' but only of the subject predisposed. It is therefore contrary to the mind of Aristotle, that the mere 'predisposition' should be the potential intellect.

4. An effect cannot stand higher above the material order than its cause. But every cognitive faculty, as such, belongs to the immaterial order. Therefore it is impossible for any cognitive faculty to be caused by a combination of elements. But the potential intellect is the supreme cognitive faculty in us: therefore it is not caused by a combination of elements.

6. No bodily organ can possibly have a share in the act of understanding. But that act is attributed to the soul, or to the man: for we say that the soul understands, or the man through the soul. Therefore there must be in man some principle independent of the body, to be the principle of such an act. But any predisposition, which is the result of a combination of elements, manifestly depends on the body. Therefore no such predisposition can be a principle like the potential intellect, whereby the soul judges and understands.

But if it is said that the principle of the aforesaid operation in us is the intellectual impression actually made by the active intellect, this does not seem to suffice: because when man comes to have actual intellectual cognition from having had such cognition potentially, he needs to understand not merely by some intelligible impression actualising his understanding, but likewise by some intellectual faculty as the principle of such activity. Besides, an impression is not in actual understanding except so far as it is purified from particular and material being. But this cannot happen so long as it remains in any material faculty, that is to say, in any faculty either caused by material principles or actualising a material organ. Therefore there must be posited in us some immaterial intellectual faculty, and that is the potential intellect.